Copolyester prepared by contacting acyloxy benzoic acid with a polyester of ethylene glycol and dicarboxylic acid

Abstract

Abstract Disclosed is a copolyester having no substantial amount of either aliphatic to aromatic oxygen linkages or aromatic to aromatic oxygen linkages, the copolyester being comprised of the following divalent radicals: WHEREIN R2 is a carbocyclic aromatic nucleus wherein the chain extending oxygen linkages are coaxial or parallel and are oppositely directed, the range of radical (C) plus radical (D) is from about 30 to about 75 mole percent, based on the total moles of radical (B), radical (C) and radical (D) combined, and the amount of radical (D) is not greater than 30 mole percent, based on the total moles of radical (B), radical (C) and radical (D) combined. The copolyesters of this invention are prepared by a process comprised of two steps. The first step comprises forming a fragmented polyester by acidolysis of a starting polyester with an acyloxy benzoic acid in the presence of a dicarboxylic acid corresponding to radical (A) and a diol corresponding to radical (D). The second step comprises increasing the inherent viscosity of the fragmented polyester to form the copolyester of the invention. The starting polyester is formed from a dicarboxylic acid corresponding to radical (A) and ethylene glycol corresponding to radical (B) and contains a repeating unit composed of radical (A) attached to radical (B). When the acyloxy benzoic acid and starting polyester are contacted in the presence of a dicarboxylic acid corresponding to radical (A), and a diol corresponding to radical (D), acidolysis occurs and a fragmented polyester is formed. The inherent viscosity of the fragmented polyester is then increased to form the copolyester of the invention comprised of radicals (A), (B), (C) and (D). Radical (A) of the copolyester is contributed from the dicarboxylic acid portion of the starting plyester and the quantity of dicarboxylic acid used in preparing the copolyester of the invention, radical (B) of the copolyester is contributed from the ethylene glycol portion of the starting polyester, radical (C) is contributed from the acyloxy benzoic acid, and the aromatic diol contributes radical (D) to the copolyester. Radical (C) will be recognized as the radical remaining after removal of the acyl and hydroxy groups from the acyloxy benzoic acid. The copolyesters of this invention exhibit unobvious mechanical properties.

Inventors

• 👤 Finley E Mcfarlane
• 👤 Thomas G Davis

Bibliographic Details